Magnetic Proximity Sensors :::
Magnetic Sensors:- Magnetic proximity sensors are characterised by the possibility of large switching distances, available from sensors with small dimensions. They detect magnetic objects (usually permanent magnets), which are used to trigger the switching process. As the magnetic fields are able to pass through many non-magnetic materials, the switching process can also be triggered without the need for direct exposure to the target object. By using magnetic conductors (e.g., iron), the magnetic field can be transmitted over greater distances so that, for example, the signal can be carried away from high temperature areas.
Proximity sensing is the technique of detecting the presence or absence of an object using a critical distance. A position sensor determines an object's coordinates (linear or angular) with respect to a reference, displacement means moving from one position to another for a specified distance (or angle). In effect, a proximity sensor is a threshold version of a position sensor.
Inductive Proximity Sensors :::
Inductive Sensors:- Inductive Proximity Switches, self contained, depend on the output of an oscillator for their operation. The oscillator resonant circuit uses an open core coil to produce a concentrated high frequency electromagnetic (RF) field, which emerges from the active surface of the sensor. If a metal target (or other electrically conductive material) enters this field, eddy currents will be induced in it, causing the resonating oscillator to be damped.
The associated electronic circuitry detects the damping of the oscillator, triggers the switching action, and amplifies the output to drive devices such as Relays, Counters, etc. When the target is removed from the sensing field, the reverse action takes place, the undamping of the oscillator is detected and the switch is returned to its original state.
Introduction - 3 Wire DC & 4 wire DC SW 3051/4051/5051/6051/7051:- These switches operate on DC voltages from 5 volts to 240 volts. Standard models operate on 10-30 V DC and can be used with Logic Circuits, Counters or to drive Relay Coil directly. The output of these switches can be either PNP or NPN or both. With PNP output, the switching is in the sourcing mode and the load must be connected between the Output and the Negative of the supply. Conversely, with NPN output the switching is in sinking mode & the load must be connected between the output & the positive of the supply. All 3 wire & 4 wire DC switches are internally protected against Inductive voltage peaks, Spurious line pulses, Reverse polarity & Short circuit conditions.
General Specifications (Standard Models)
10 to 30 V DC
|Reverse Polarity Protection|
Provided for all models.
|Short Circuit Protection|
Provided for sizes M8 & above.
-25°C to 70°C
Green LED for PNP, Red LED for NPN